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Author Fonseca, R.M.; Hirsch, M.; Srivastava, R.
Title Delta L=3 processes: Proton decay and the LHC Type Journal Article
Year 2018 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 97 Issue 7 Pages 075026 - 7pp
Keywords
Abstract (up) We discuss lepton number violation in three units. From an effective field theory point of view, Delta L = 3 processes can only arise from dimension 9 or higher operators. These operators also violate baryon number, hence many of them will induce proton decay. Given the high dimensionality of these operators, in order to have a proton half-life in the observable range, the new physics associated to Delta L = 3 processes should be at a scale as low as 1 TeV. This opens up the possibility of searching for such processes not only in proton decay experiments but also at the LHC. In this work we analyze the relevant d = 9, 11, 13 operators which violate lepton number in three units. We then construct one simple concrete model with interesting low- and high-energy phenomenology.
Address [Fonseca, Renato M.; Hirsch, Martin; Srivastava, Rahul] Univ Valencia, CSIC, Inst Fis Corpuscular, AHEP Grp, Parc Cient Paterna,C Catedrat Jose Beltran 2, E-46980 Paterna, Valencia, Spain, Email: renato.fonseca@ific.uv.es;
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2470-0010 ISBN Medium
Area Expedition Conference
Notes WOS:000430459800005 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 3560
Permanent link to this record
 
 
Author Richard, J.M.; Valcarce, A.; Vijande, J.
Title Few-body quark dynamics for doubly heavy baryons and tetraquarks Type Journal Article
Year 2018 Publication Physical Review C Abbreviated Journal Phys. Rev. C
Volume 97 Issue 3 Pages 035211 - 10pp
Keywords
Abstract (up) We discuss the adequate treatment of the three- and four-body dynamics for the quark model picture of double-charm baryons and tetraquarks. We stress that the variational and Born-Oppenheimer approximations give energies very close to the exact ones, while the diquark approximation might be somewhat misleading. The Hall-Post inequalities also provide very useful lower bounds that exclude the possibility of stable tetraquarks for some mass ratios and some color wave functions.
Address [Richard, Jean-Marc] Univ Lyon, Inst Phys Nucl Lyon, CNRS UCBL IN2P3, 4 Rue Enrico Fermi, F-69622 Villeurbanne, France, Email: j-m.richard@ipnl.in2p3.fr;
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2469-9985 ISBN Medium
Area Expedition Conference
Notes WOS:000428505400005 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3543
Permanent link to this record
 
 
Author Fonseca, R.M.; Hirsch, M.
Title Delta L >= 4 lepton number violating processes Type Journal Article
Year 2018 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 98 Issue 1 Pages 015035 - 12pp
Keywords
Abstract (up) We discuss the experimental prospects for observing processes which violate lepton number (Delta L) in four units ( or more). First, we reconsider neutrinoless quadruple beta decay, deriving a model independent and very conservative lower limit on its half- life of the order of 10(41) ys for Nd-150. This renders quadruple beta decay unobservable for any feasible experiment. We then turn to a more general discussion of different possible low-energy processes with values Delta L >= 4. A simple operator analysis leads to rather pessimistic conclusions about the observability at low-energy experiments in all cases we study. However, the situation looks much brighter for accelerator experiments. For two example models with Delta L = 4 and another one with Delta L = 5, we show how the LHC or a hypothetical future pp collider, such as the FCC, could probe multilepton number violating operators at the TeV scale.
Address [Fonseca, Renato M.; Hirsch, Martin] Univ Valencia, CSIC, Inst Fis Corpuscular, AHEP Grp, Spain Edificio Inst Paterna,Apartado 22085, E-46071 Valencia, Spain, Email: renato.fonseca@ific.uv.es;
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2470-0010 ISBN Medium
Area Expedition Conference
Notes WOS:000439791500005 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 3675
Permanent link to this record
 
 
Author Fileviez Perez, P.; Murgui, C.
Title Dark matter and the seesaw scale Type Journal Article
Year 2018 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 98 Issue 5 Pages 055008 - 9pp
Keywords
Abstract (up) We discuss the possibility of finding an upper hound on the seesaw scale using the cosmological bound on the cold dark matter relic density. We investigate a simple relation between the origin of neutrino masses and the properties of a dark matter candidate in a simple theory where the new symmetry breaking scale defines the seesaw scale. Imposing the cosmological hounds, we find an upper bound of order multi-TeV on the lepton number violation scale. We investigate the predictions for direct and indirect detection dark matter experiments and the possible signatures at the Large Hadron Collider.
Address [Perez, Pavel Fileviez] Case Western Reserve Univ, Phys Dept, Rockefeller Bldg,2076 Adelbert Rd, Cleveland, OH 44106 USA
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2470-0010 ISBN Medium
Area Expedition Conference
Notes WOS:000444208700010 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3738
Permanent link to this record
 
 
Author Valcarce, A.; Vijande, J.; Richard, J.M.; Garcilazo, H.
Title Stability of Heavy Tetraquarks Type Journal Article
Year 2018 Publication Few-Body Systems Abbreviated Journal Few-Body Syst.
Volume 59 Issue 2 Pages 9 - 7pp
Keywords
Abstract (up) We discuss the stability of tetraquark systems with two different masses. After some reminders about the stability of very asymmetric QQ (q) over bar(q) over bar tetraquarks, we demonstrate that in the all-heavy limit q -> Q, the system becomes unstable for standard color-additive models. We also analyze the consequences of symmetry breaking for Qq (Q) over bar(q) over bar configurations: we find a kind of metastability between the lowest threshold Q (Q) over bar + q (q) over bar and the highest one, Q (q) over bar + (Q) over barq, and we calculate the width of the resonance. Our results are consistent with the experimental observation of narrow hadrons lying well above their lowest decay threshold.
Address [Valcarce, A.] Univ Salamanca, Dept Fis Fundamental, E-37008 Salamanca, Spain, Email: valcarce@usal.es;
Corporate Author Thesis
Publisher Springer Wien Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0177-7963 ISBN Medium
Area Expedition Conference
Notes WOS:000427011200005 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3574
Permanent link to this record
 
 
Author Srivastava, R.; Ternes, C.A.; Tortola, M.; Valle, J.W.F.
Title Zooming in on neutrino oscillations with DUNE Type Journal Article
Year 2018 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 97 Issue 9 Pages 095025 - 11pp
Keywords
Abstract (up) We examine the capabilities of the DUNE experiment as a probe of the neutrino mixing paradigm. Taking the current status of neutrino oscillations and the design specifications of DUNE, we determine the experiment's potential to probe the structure of neutrino mixing and CP violation. We focus on the poorly determined parameters theta(23) and delta(cp) and consider both two and seven years of run. We take various benchmarks as our true values, such as the current preferred values of theta(23) and delta(cp), as well as several theory-motivated choices. We determine quantitatively DUNE's potential to perform a precision measurement of theta(23), as well as to test the CP violation hypothesis in a model-independent way. We find that, after running for seven years, DUNE will make a substantial step in the precise determination of these parameters, bringing to quantitative test the predictions of various theories of neutrino mixing.
Address [Srivastava, Rahul; Ternes, Christoph A.; Tortola, Mariam; Valle, Jose W. F.] Univ Valencia, CSIC, Inst Fis Corpuscular, AHEP Grp, Parc Cient Paterna C Catedrat Jose Beltran 2, E-46980 Paterna, Valencia, Spain, Email: rahulsri@ific.uv.es;
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2470-0010 ISBN Medium
Area Expedition Conference
Notes WOS:000433027600011 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 3580
Permanent link to this record
 
 
Author Kuo, J.L.; Lattanzi, M.; Cheung, K.; Valle, J.W.F.
Title Decaying warm dark matter and structure formation Type Journal Article
Year 2018 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.
Volume 12 Issue 12 Pages 026 - 24pp
Keywords cosmological simulations; dark matter simulations
Abstract (up) We examine the cosmology of warm dark matter (WDM), both stable and decaying, from the point of view of structure formation. We compare the matter power spectrum associated to WDM masses of 1.5 keV and 0.158 keV, with that expected for the stable cold dark matter ACDM Xi SCDM paradigm, taken as our reference model. We scrutinize the effects associated to the warm nature of dark matter, as well as the fact that it decays. The decaying warm dark matter (DWDM) scenario is well-motivated, emerging in a broad class of particle physics theories where neutrino masses arise from the spontaneous breaking of a continuous global lepton number symmetry. The majoron arises as a Nambu-Goldstone boson, and picks up a mass from gravitational effects, that explicitly violate global symmetries. The majoron necessarily decays to neutrinos, with an amplitude proportional to their tiny mass, which typically gives it cosmologically long lifetimes. Using N-body simulations we show that our DWDM picture leads to a viable alternative to the ACDM scenario, with predictions that can differ substantially on small scales.
Address [Kuo, Jui-Lin; Cheung, Kingman] Natl Tsing Hua Univ, Dept Phys, Hsinchu, Taiwan, Email: juilinkuo@gapp.nthu.edu.tw;
Corporate Author Thesis
Publisher Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1475-7516 ISBN Medium
Area Expedition Conference
Notes WOS:000453858100005 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3851
Permanent link to this record
 
 
Author Witte, S.; Villanueva-Domingo, P.; Gariazzo, S.; Mena, O.; Palomares-Ruiz, S.
Title EDGES result versus CMB and low-redshift constraints on ionization histories Type Journal Article
Year 2018 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 97 Issue 10 Pages 103533 - 8pp
Keywords
Abstract (up) We examine the results from the Experiment to Detect the Global Epoch of Reionization Signature (EDGES), which has recently claimed the detection of a strong absorption in the 21 cm hyperfine transition line of neutral hydrogen, at redshifts demarcating the early stages of star formation. More concretely, we study the compatibility of the shape of the EDGES absorption profile, centered at a redshift of z similar to 17.2, with measurements of the reionization optical depth, the Gunn-Peterson optical depth, and Lyman-alpha emission from star-forming galaxies, for a variety of possible reionization models within the standard ACDM framework (that is, a Universe with a cosmological constant. and cold dark matter CDM). When, conservatively, we only try to accommodate the location of the absorption dip, we identify a region in the parameter space of the astrophysical parameters that successfully explains all of the aforementioned observations. However, one of the most abnormal features of the EDGES measurement is the absorption amplitude, which is roughly a factor of 2 larger than the maximum allowed value in the ACDM framework. We point out that the simple considered astrophysical models that produce the largest absorption amplitudes are unable to explain the depth of the dip and of reproducing the observed shape of the absorption profile.
Address [Witte, Samuel; Villanueva-Domingo, Pablo; Gariazzo, Stefano; Mena, Olga; Palomares-Ruiz, Sergio] Univ Valencia, CSIC, Inst Fis Corpuscular IFIC, Apartado Correos 22085, E-46071 Valencia, Spain
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2470-0010 ISBN Medium
Area Expedition Conference
Notes WOS:000433291600010 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 3606
Permanent link to this record
 
 
Author Vagnozzi, S.; Dhawan, S.; Gerbino, M.; Freese, K.; Goobar, A.; Mena, O.
Title Constraints on the sum of the neutrino masses in dynamical dark energy models with w(z) >=-1 are tighter than those obtained in Lambda CDM Type Journal Article
Year 2018 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 98 Issue 8 Pages 083501 - 20pp
Keywords
Abstract (up) We explore cosmological constraints on the sum of the three active neutrino masses M-v in the context of dynamical dark energy (DDE) models with equation of state (EoS) parametrized as a function of redshift z by w(z) = w(0) + w(a)z/ (1 + z), and satisfying w(z) >= -1 for all z. We make use of cosmic microwave background data from the Planck satellite, baryon acoustic oscillation measurements, and supernovae la luminosity distance measurements, and perform a Bayesian analysis. We show that, within these models, the bounds on M-v do not degrade with respect to those obtained in the Lambda CDM case; in fact, the bounds arc slightly tighter, despite the enlarged parameter space. We explain our results based on the observation that, for fixed choices of w(0), w(a) such that w(z) >= -1 (but not w = -1 for all z), the upper limit on M-v is tighter than the Lambda CDM limit because of the well-known degeneracy between w and M-v. The Bayesian analysis we have carried out then integrates over the possible values of w(0)-w(a) such that w(z) >= -1, all of which correspond to tighter limits on M-v than the Lambda CDM limit. We find a 95% credible interval (C.I.) upper bound of M-v < 0.13 eV. This bound can be compared with the 95% C.I. upper bounds of M-v < 0.16 eV, obtained within the Lambda CDM model, and M-v < 0.41 eV, obtained in a DDE model with arbitrary EoS (which allows values of w < -1). Contrary to the results derived for DDE models with arbitrary EoS, we find that a dark energy component with w(z) >= -1 is unable to alleviate the tension between high-redshift observables and direct measurements of the Hubble constant H o . Finally, in light of the results of this analysis, we also discuss the implications for DDE models of a possible determination of the neutrino mass ordering by laboratory searches.
Address [Vagnozzi, Sunny; Dhawan, Suhail; Gerbino, Martina; Freese, Katherine; Goobar, Ariel] Stockholm Univ, Oskar Klein Ctr Cosmoparticle Phys, Dept Phys, SE-10691 Stockholm, Sweden, Email: sunny.vagnozzi@fysik.su.se
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2470-0010 ISBN Medium
Area Expedition Conference
Notes WOS:000446136900001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3749
Permanent link to this record
 
 
Author Escudero, M.; Witte, S.J.; Rius, N.
Title The dispirited case of gauged U(1)(B-L) dark matter Type Journal Article
Year 2018 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 08 Issue 8 Pages 190 - 30pp
Keywords Beyond Standard Model; Cosmology of Theories beyond the SM
Abstract (up) We explore the constraints and phenomenology of possibly the simplest scenario that could account at the same time for the active neutrino masses and the dark matter in the Universe within a gauged U(1)(B-L) symmetry, namely right-handed neutrino dark matter. We find that null searches from lepton and hadron colliders require dark matter with a mass below 900 GeV to annihilate through a resonance. Additionally, the very strong constraints from high-energy dilepton searches fully exclude the model for 150 GeV < m(z') < 3 TeV. We further explore the phenomenology in the high mass region (i.e. masses greater than or similar to O(1) TeV) and highlight theoretical arguments, related to the appearance of a Landau pole or an instability of the scalar potential, disfavoring large portions of this parameter space. Collectively, these considerations illustrate that a minimal extension of the Standard Model via a local U(1)(B-L) symmetry with a viable thermal dark matter candidate is difficult to achieve without fine-tuning. We conclude by discussing possible extensions of the model that relieve tension with collider constraints by reducing the gauge coupling required to produce the correct relic abundance.
Address [Escudero, Miguel] Univ Valencia, CSIC, Dept Fis Teor, C Catedrat Jose Beltran 2, E-46980 Paterna, Spain, Email: Miguel.Escudero@ific.uv.es;
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:000443008100006 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 3706
Permanent link to this record